The utilization of multiple tube and shell type heat exchangers for the heating or cooling of liquid products is well known; however, where the product is flowing through the tubes in such an exchanger under high pressures, one or more of the following problems have been encountered:
(a) Maintaining proper sealing of the high pressure tubes to maintain the product and the heat exchange medium separate while both are flowing through the exchanger;
(b) Compensating for the expansion and contraction of the tubes;
(c) Relatively short lengths of tubular sections are required to minimize the expansion or contraction effect and thus, necessitates an inordinate number of welded connections between the sections as well as between the tubes and the shell thereby significantly increasing the installation and maintenance costs.